QR Code Size Guide: How Big Should a QR Code Be?

The number one reason a printed QR code fails isn't the code — it's the size. A perfectly generated, high-contrast code still won't scan from a table away if it's printed the size of a fingernail. Here are the rules that actually matter, plus a calculator for your exact case.

The 10:1 rule (the one to remember)

Minimum code size ≈ scanning distance ÷ 10.

Scanning distance	Minimum QR code size
10 cm / 4 in (held in hand)	1 cm / 0.4 in — anything bigger is comfortable
50 cm / 20 in (across a counter)	5 cm / 2 in
1 m / 3 ft (arm's length, table)	10 cm / 4 in
2 m / 6 ft (store shelf)	20 cm / 8 in
5 m / 16 ft (window, aisle)	50 cm / 20 in
10 m / 33 ft (billboard range)	1 m / 40 in

This is the scan-distance rule used across the industry (Denso Wave, the QR inventor, suggests a similar ratio, commonly cited as distance-to-symbol ratio of roughly 10:1 for standard cameras). It assumes an average phone camera and average eyesight; a large, dense code at the edge of its range is exactly where "works on my phone" and "doesn't work on theirs" diverge.

Absolute minimums

Even for hand-distance scanning, don't go below:

• 2 × 2 cm (0.8 × 0.8 in) — the practical floor for any printed code. Below this, cameras struggle to resolve the module grid.
• On business cards: 2.5 × 2.5 cm (1 in) works comfortably; 3 cm is friendlier. See QR codes for business cards.

And remember the quiet zone: the blank margin around the code (officially four modules wide) is part of the size. Don't let design elements crowd it.

Module size — the detail that decides everything

A QR code is a grid of modules (see how QR codes work), and what a camera actually resolves is the module, not the code. Rules of thumb:

• Each module should print at ≥ 0.4 mm for close scanning; ≥ 0.75 mm for distance scanning
• More content = more modules = must print bigger. A short URL (25 × 25 grid) at 2 cm wide has 0.8 mm modules — fine. A full contact card (53 × 53 grid) at 2 cm has 0.38 mm modules — already marginal. Same printed size, different outcome.

That's the hidden coupling between content and print: keep content short and your code gets scannable-small for free. This is also why adding a logo or raising error correction (which increases density) affects minimum size.

Digital screens

On screens, resolution does the work of physical size:

• Websites and email: 200–300 px renders crisply on phones and scales fine
• Presentations: 300+ px, and test from the back row — a projector at 10 m needs the same 10:1 math as print
• Never scale up a small raster image. A 100 px PNG blown up to 500 px is a blurry mess cameras resent. Use the SVG for scaling, or export the PNG at the size you need (the generator exports PNG up to 2048 px)

Print-shop specifics

• Vector (SVG/EPS) beats raster for print. No pixelation at any size; every print shop handles SVG
• 300 DPI minimum for raster. A 2 cm code at 300 DPI is ~236 px — so even 512 px exports cover small prints; use 1024–2048 for anything else
• Ink spread: cheap or absorbent printing slightly fattens dark modules. Keep contrast high and modules comfortably above minimum
• Test the actual proof. Scan the printer's proof at the real distance before approving the run

Common formats, recommended sizes

Use case	Recommended size
Business card	2.5–3 cm / 1–1.2 in
Flyer / handout	3–4 cm / 1.2–1.6 in
Table tent / menu	4–5 cm / 1.6–2 in
A4 poster (1–2 m)	10–20 cm / 4–8 in
Product packaging	2.5–4 cm depending on viewing distance
Shop window (street)	20+ cm / 8+ in
Vehicle / billboard	50–100+ cm / 20–40+ in

Squeezing more range from a given size

If you can't print bigger:

1. Shorten the content — fewer modules means bigger modules at the same physical size (the single most effective trick)
2. Drop to error correction M or L — fewer codewords, simpler pattern (weigh this against damage risk — see how QR codes work)
3. Maximize contrast — near-black on white
4. Keep the quiet zone full — never trim the margin to make the pattern itself bigger

The pre-print checklist

• Code is at least distance ÷ 10
• Modules ≥ 0.4 mm (close) or ≥ 0.75 mm (far)
• Quiet zone intact — four modules of blank border
• High contrast, right way round (dark code on light background)
• Scanned successfully from a real phone at the real distance, on the real print

Generate your code at the right size: the QR generator exports print-ready PNG and SVG, and the printing guide covers materials, finishes and file formats in detail.